Hi
1) Generally for martial disputes, extradition orders are not issued.
2) Supreme court in Arnesh Kumar Vs. State of Bihar, 2014 (8) SCC 273 has categorically stated that there shall be No Automatic Arrest in 498A Cases and strict Guidelines have been issued to Police And Magistrates.
3) Your daughter in law can file 498a and Domestic violence cases against your son and you(father and mother).
4) If your son's wife chooses to file a 498a(dowry case) against you, then you and your son can appear in front of police and submit your statement denying the allegations.
5) Another Alternative remedy is that if your daughter in law files 498a and Domestic violence cases, you can get the same quashed by filing a petition under section 482 of Cr.P.C at Delhi High court.
7) You can also petition the Delhi High court under section 482 of Cr.P.C for exemption from personal appearance etc.
Hope this information is useful.